Objective To explore the effect and mechanism of Sechang Zhixie Powder(SCZXS)on mice with acute diarrhea caused by castor oil.Methods The mice were randomly divided into blank control group,model control group,montmorillonite powder group(1.4 g·kg-1),SCZXS-L group(0.9 g·kg-1),SCZXS-M group(1.8 g·kg-1)and SCZXS-H group(3.6 g·kg-1),10 mice in each group.After continuous administration of 7 days,the acute diarrhea model of mice was prepared by oral administration of castor oil(0.01 mL·g-1).The diarrhea of mice was observed within 4 hours of castor oil administration,and the rate of loose stool,degree of loose stool,and diarrhea index were calculated;the levels of DAO,D-LDH,VIP,and SS in the colon were determined by enzyme-linked immunosorbent assay;The morphological changes in the colon tissue of mice were observed after HE staining and the thicknesses of the mucosal and muscular layers of the colon were quantified;AB-PAS staining was performed to observe the effect on mucin in the colon;and the expression of AQP3,Occludin,and ZO-1 in the colon were quantified by immunohistochemistry.Results Compared with the model control group,the rate of loose stool,degree of loose stool,and diarrhea index of the mice in the SCZXS groups tended to decrease,but the difference was not statistically significant.Compared with the model control group,the flat luminal surface of the mice in the SCZXS-M and SCZXS-H group were significantly thickened(P<0.01),and the amount of VIP in the colon was significantly decreased(P<0.05,P<0.01),and that of DAO in the colon was significantly decreased(P<0.01),Occludin and ZO-1 expression were significantly increased(P<0.01),the mucin area ratio was significantly increased(P<0.05)in the SCZXS-M group,and AQP3 expression was significantly increased(P<0.05)in the SCZXS groups.Conclusions SCZXS can improve acute diarrhea induced by castor oil in mice.and its mechanism may be related to the regulation of gastrointestinal hormones and AQP3.In addition,SCZXS improves intestinal damage caused by diarrhea and protects the intestinal barrier.

Objective:? To summarize the achievements in improving the consistency of clinical liquid chromatography-tandem mass spectrometry (LC-MS/MS) testing results.Methods:? From 2021 to 2024, Zhongshan Hospital Affiliated to Fudan University recruited laboratories voluntarily participating in the MSHP (Clinical LC-MS/MS Testing Consistency Program). As of Batch 202404, a total of 76 laboratories had enrolled, including 60 medical institutions (all tertiary hospitals) and 16 third-party laboratories. Test items were established, and comparative samples were distributed regularly-each item′s samples covered three concentrations (high, medium, and low). Samples were shipped via cold chain and tested within one week. Our laboratory′s measurements served as the target, with participating labs′ results within ±25% of the target deemed qualified. Passing-Bablok regression and Bland-Altman analysis were used to assess consistency.Results:Taking 3-MT (3-methoxytyramine) as an example, the coefficients of variation (CVs) for the project′s three concentration levels improved from 17.00%, 47.18%, and 4.88% in the first comparative batch to 9.59%, 9.59%, and 6.1% in Batch 202404. Passing-Bablok regression results for the 5 units participating in 3-MT testing showed that Laboratory A had proportional bias but no systematic bias (regression slope [95% CI]: 0.903 [0.862-0.952]; intercept [95% CI]: 0.912 [-1.921-6.073]). The remaining laboratories exhibited no proportional or systematic bias with the target (Laboratory B: slope 1.031 [0.961-1.147], intercept-0.733 [-4.641-8.272]; Laboratory C: slope 0.982 [0.940-1.009], intercept-0.576 [-2.675-1.891]; Laboratory D: slope 0.973 [0.939-1.066], intercept-1.168 [-6.108-1.649]; Laboratory E: slope 0.999 [0.905-1.051], intercept-1.876 [-6.111-3.508]). Bland-Altman analysis indicated that all 5 laboratories′ results generally showed good consistency with the target. Through quality feedback and optimizing sample preparation concentrations, result consistency was enhanced.? Conclusion:? Clinical LC-MS/MS testing consistency programs contribute to improving the comparability of test results.

Objective To establish and validate a method for simultaneous analysis of fluconazole,linezolid,voriconazole and cont-ezolid by liquid chromatography-tandem mass spectrometry,and conduct preliminary assessment its value of application value in clinical therapeutic drug monitoring.Methods Using an isotopic internal standard method,the serum samples were pretreated with protein precipitation.The supernatant was diluted after centrifugation,and detected by liquid chromatography-tandem mass spectrometer.Refer-ring to the Recommendations for Clinical Application of Liquid Chromatography-Mass Spectrometry(LC-MS)and Clinical and Labora-tory Standards Instituhe(CLSI)C62A,the performance of the LC-MS method was verified,including quantitation limits,linearity,trueness,precision,matrix effect,carry-over,interference,dilution consistency and stability.The blood samples from patients who were treated with fluconazole,linezolid,voriconazole,and contezolid were collected and measured for trough or peak concentrations.Results The quantitation limits of fluconazole,linezolid,voriconazole and contezolid by this method were 1 μg/mL,0.25 μg/mL,0.25 μg/mL and 0.1 μg/mL,respectively.The linear ranges were 1-100 μg/mL,0.25-25 μg/mL,0.25-25 μg/mL,and 0.1-10μg/mL,respectively.The recovery rates were 103.0％-105.7％,103.1％-108％,102.4％-106.2％and 101.0％-109.9％,respectively.The precisions,expressed as coefficient of variation(CV),were 1.7％-3.4％,2.1％-4.8％,1.9％-3.1％,and 3.1％-6.8％,respective-ly.No obvious matrix effect,carry-over contamination and interference were found.The dilution consistency and stability were satisfac-tory.The concentrations of fluconazole,linezolid and voriconazole within the reference interval accounted for 49.1％,52.5％and 80.7％of the total samples,respectively.The peak concentration of contezolamide was(14.02±4.94)μg/mL(n=4),and the trough concen-tration was(0.34±0.20)μg/mL(n=5).Conclusion In this study,a method for simultaneous analysis of the concentrations of flu-conazole,linezolid,voriconazole and contezolid was successfully established and verified by liquid chromatography-tandem mass spec-trometry.This method is simple,rapid,and suitable for therapeutic drug monitoring,and providing a basis for the optimization of drug regimens.

Objective:? To summarize the achievements in improving the consistency of clinical liquid chromatography-tandem mass spectrometry (LC-MS/MS) testing results.Methods:? From 2021 to 2024, Zhongshan Hospital Affiliated to Fudan University recruited laboratories voluntarily participating in the MSHP (Clinical LC-MS/MS Testing Consistency Program). As of Batch 202404, a total of 76 laboratories had enrolled, including 60 medical institutions (all tertiary hospitals) and 16 third-party laboratories. Test items were established, and comparative samples were distributed regularly-each item′s samples covered three concentrations (high, medium, and low). Samples were shipped via cold chain and tested within one week. Our laboratory′s measurements served as the target, with participating labs′ results within ±25% of the target deemed qualified. Passing-Bablok regression and Bland-Altman analysis were used to assess consistency.Results:Taking 3-MT (3-methoxytyramine) as an example, the coefficients of variation (CVs) for the project′s three concentration levels improved from 17.00%, 47.18%, and 4.88% in the first comparative batch to 9.59%, 9.59%, and 6.1% in Batch 202404. Passing-Bablok regression results for the 5 units participating in 3-MT testing showed that Laboratory A had proportional bias but no systematic bias (regression slope [95% CI]: 0.903 [0.862-0.952]; intercept [95% CI]: 0.912 [-1.921-6.073]). The remaining laboratories exhibited no proportional or systematic bias with the target (Laboratory B: slope 1.031 [0.961-1.147], intercept-0.733 [-4.641-8.272]; Laboratory C: slope 0.982 [0.940-1.009], intercept-0.576 [-2.675-1.891]; Laboratory D: slope 0.973 [0.939-1.066], intercept-1.168 [-6.108-1.649]; Laboratory E: slope 0.999 [0.905-1.051], intercept-1.876 [-6.111-3.508]). Bland-Altman analysis indicated that all 5 laboratories′ results generally showed good consistency with the target. Through quality feedback and optimizing sample preparation concentrations, result consistency was enhanced.? Conclusion:? Clinical LC-MS/MS testing consistency programs contribute to improving the comparability of test results.

Objective To explore the effect and mechanism of Sechang Zhixie Powder(SCZXS)on mice with acute diarrhea caused by castor oil.Methods The mice were randomly divided into blank control group,model control group,montmorillonite powder group(1.4 g·kg-1),SCZXS-L group(0.9 g·kg-1),SCZXS-M group(1.8 g·kg-1)and SCZXS-H group(3.6 g·kg-1),10 mice in each group.After continuous administration of 7 days,the acute diarrhea model of mice was prepared by oral administration of castor oil(0.01 mL·g-1).The diarrhea of mice was observed within 4 hours of castor oil administration,and the rate of loose stool,degree of loose stool,and diarrhea index were calculated;the levels of DAO,D-LDH,VIP,and SS in the colon were determined by enzyme-linked immunosorbent assay;The morphological changes in the colon tissue of mice were observed after HE staining and the thicknesses of the mucosal and muscular layers of the colon were quantified;AB-PAS staining was performed to observe the effect on mucin in the colon;and the expression of AQP3,Occludin,and ZO-1 in the colon were quantified by immunohistochemistry.Results Compared with the model control group,the rate of loose stool,degree of loose stool,and diarrhea index of the mice in the SCZXS groups tended to decrease,but the difference was not statistically significant.Compared with the model control group,the flat luminal surface of the mice in the SCZXS-M and SCZXS-H group were significantly thickened(P<0.01),and the amount of VIP in the colon was significantly decreased(P<0.05,P<0.01),and that of DAO in the colon was significantly decreased(P<0.01),Occludin and ZO-1 expression were significantly increased(P<0.01),the mucin area ratio was significantly increased(P<0.05)in the SCZXS-M group,and AQP3 expression was significantly increased(P<0.05)in the SCZXS groups.Conclusions SCZXS can improve acute diarrhea induced by castor oil in mice.and its mechanism may be related to the regulation of gastrointestinal hormones and AQP3.In addition,SCZXS improves intestinal damage caused by diarrhea and protects the intestinal barrier.

Objective To establish and validate a method for simultaneous analysis of fluconazole,linezolid,voriconazole and cont-ezolid by liquid chromatography-tandem mass spectrometry,and conduct preliminary assessment its value of application value in clinical therapeutic drug monitoring.Methods Using an isotopic internal standard method,the serum samples were pretreated with protein precipitation.The supernatant was diluted after centrifugation,and detected by liquid chromatography-tandem mass spectrometer.Refer-ring to the Recommendations for Clinical Application of Liquid Chromatography-Mass Spectrometry(LC-MS)and Clinical and Labora-tory Standards Instituhe(CLSI)C62A,the performance of the LC-MS method was verified,including quantitation limits,linearity,trueness,precision,matrix effect,carry-over,interference,dilution consistency and stability.The blood samples from patients who were treated with fluconazole,linezolid,voriconazole,and contezolid were collected and measured for trough or peak concentrations.Results The quantitation limits of fluconazole,linezolid,voriconazole and contezolid by this method were 1 μg/mL,0.25 μg/mL,0.25 μg/mL and 0.1 μg/mL,respectively.The linear ranges were 1-100 μg/mL,0.25-25 μg/mL,0.25-25 μg/mL,and 0.1-10μg/mL,respectively.The recovery rates were 103.0％-105.7％,103.1％-108％,102.4％-106.2％and 101.0％-109.9％,respectively.The precisions,expressed as coefficient of variation(CV),were 1.7％-3.4％,2.1％-4.8％,1.9％-3.1％,and 3.1％-6.8％,respective-ly.No obvious matrix effect,carry-over contamination and interference were found.The dilution consistency and stability were satisfac-tory.The concentrations of fluconazole,linezolid and voriconazole within the reference interval accounted for 49.1％,52.5％and 80.7％of the total samples,respectively.The peak concentration of contezolamide was(14.02±4.94)μg/mL(n=4),and the trough concen-tration was(0.34±0.20)μg/mL(n=5).Conclusion In this study,a method for simultaneous analysis of the concentrations of flu-conazole,linezolid,voriconazole and contezolid was successfully established and verified by liquid chromatography-tandem mass spec-trometry.This method is simple,rapid,and suitable for therapeutic drug monitoring,and providing a basis for the optimization of drug regimens.

Objective:The aim of this study was to develop and validate a new liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay for the quantification of melatonin in human serum.Methods:We describe the performance and validation of melatonin by LC-MS/MS. 182 serum samples from the patients diagnosed with Sleep disturbance who visited the Department of Psychiatry at Zhongshan Hospital affiliated to Fudan University from February 2022 to March 2023(56 males,162 females,mean age [45.51±16.31]years), as well as 182 healthy individuals were included(87 males,95 females,mean age [48.55±11.93]years). The two groups were used to assess the application of serum melatonin levels as a diagnostic indicator for sleep disorders (SDs). The liquid chromatography mass spectrometry (LC-MS) system with an chromatography column (2.1×100 mm, 1.8 μm) was used for separation. The column temperature was set at 35 ℃, as well as the mobile phase consisting of a 0.1% formic acid aqueous solution and pure acetonitrile. The flowing rate was set at 0.4 ml/min for gradient elution. The LC-MS/MS method was validated according to guidance documents, including the following parameters: specificity, selectivity, matrix effect, carryover contamination and reproducibility, lower limit of measuring interval, linearity, precision, recovery rate, dilution consistency, and serum sample stability. Then, it was subsequently employed to profile melatonin changes in Sleep disturbance.Results:The lower limit of quantification for melatonin was 1 pg/ml, and the linear range of detection was 1 pg/ml to 500 pg/ml ( r=0.999). The intra-day and intra-batch precision, expressed as the coefficient of variation ( CV), was within the range from 3.07% to 6.86%, which met the requirement of less than 15%. The recovery rate of the spiked samples ranged from 105.91% to 116.30%. The level of serum melatonin in the sleep disturbance group was significantly lower than that in the healthy control group ([2.00(1.00,3.28)] vs [8.35(4.28,14.80)] pg/ml, P<0.001). Conclusions:The LC-MS/MS method we developed for the quantification of melatonin is clinical practicable.

Objective We are going to establish a robust liquid chromatography-tandem mass spectrometric(LC-MS/MS) method for plasma aldosterone assay.Methods 324 healthy individuals were enrolled in Zhongshan Hospital from February to April in 2016 for reference interval survey.The signallinearity,lower limits of quantitation,precision and accuracy of LC-MS/MS have been evaluated.Results from LC-MS/MS and RIA methods were compared.Software SPSS17.0 software was used for statistical analysis.Results The performance characteristics for the method in terms of linearity,lowerlimits of quantitation,precision and accuracy were verified.Linear range of ALD were between 25-2000 pg/ml;the LC-MS/MS assay had a limit of quantitation of 20 pg/ml for ALD;the intra-and inter-assay CV of ALD were ＜10％ and ＜6％,respectively;the recovery of ALD from serum samples ranged between 97.3 and 105.8％ The reference value of ALD in health people ranged between 21-211.6 pg/ml The regression equation by LC-MS/MS (X) and RIA (Y) was:Y =0.271X + 138.900(r=0.43;n=322).Conclusion LC-MS/MS method is robust and reliable for the analysis of aldosterone in plasma and suitable for clinical application.

Background Accurate measurement of corneal thickness is very important during the pre-and post-operative management of corneal surgical procedures,especially laser-assisted in-situ keratomileusis (LASIK),which is the most popular approach to the correction of refractive errors currently.This may be particularly important for the patients who have undergone previous laser refractive surgery with suboptimal outcomes and are being considered for an enhancement procedure.Objective This study was to compare the measuring outcomes of corneal thickness by slit-scanning pachymetry,non-contact specular microscope,anterior segment optical coherence tomography (AS-OCT)and ultrasound pachymetry,with a focus on central and midperipheral (from the central 3.0 mm) region of cornea in post-LASIK eyes.Methods Sixty-four right eyes of 64 patients who received LASIK were collected in Henan Eye Institute,Henan Eye Hospital from March to June 2011 with the equivalent spherical diopter of (-4.75±2.38)D and horizontal corneal diameter of (11.36±0.32)mm.Central corneal thickness was measured on each eye by using non-contact specular microscope (Topcon SP-3000P),slit-scanning pachymetry (Orbscan Ⅱ),AS-OCT and A-type ultrasound pachymetry,respectively,and the paracentral corneal thickness including 12:00,2:00,6:00 and 10:00 meridian was measured using Orbscan Ⅱ,non-contact specular microscope and AS-OCT.The measuring values and the agreement from different instruments were compared and evaluated.Results The mean central corneal thickness was (467.12±31.10)tμm for AS-OCT,(466.67±30.99)μm for ultrasound pachymetry,(441.84 ± 33.65) μm for specular microscopy and (422.51 ± 44.09) μm for Orbsan Ⅱ,respectively,showing a significant difference among the four methods (F =23.730,P =0.000).The central thickness value of the A-type ultrasound pachymetry was significantly higher than that of Orbsan Ⅱ or non-contact specular microscope (q =6.940,6.720,both at P =0.000).Compared with Orbscan Ⅱ,the measuring values of non-contact specular microscope and AS-OCT were significantly higher (q =-5.54,6.940,both at P =0.000),and the measuring value of AS-OCT was significantly higher that of non-contact specular microscope (q =6.800,P =0.000).The lowest difference value (25.3 μm)and the best agreement was found between the ultrasound pachymetry and AS-OCT.The paracentral corneal thickness values in 12:00,2:00,10:00,6:00 meridians were highest for Orbsan Ⅱ and the next for AS-OCT,and non-contact specular microscope had the lowest values,with significantly differences among them (F =5.020,22.950,67.890,18.850,all at P ＜ 0.01).Conclusions The corneal thickness values vary with the different instruments.Orbsan Ⅱ underestimates the central corneal thickness and overestimates the midperipheral corneal thickness,and non-contact specular microscope underestimates both the central and midperipheral corneal thickness.The measuring outcome from AS-OCT has a good agreement with ultrasound pachymetry and therefore they can be used interchangeably.